The hellish journey of the photon. The photon, created in the solar core carries the light rays to Earth, but it must pass through the radiative zone, convection zone, photosphere, chromosphere, and finally the solar corona, a trip 100 000 years.

The general public knows the signs of the zodiac in astrology. The Zodiac is the name of the area where heavens are observed movements of the Sun and planets. In fact, the ecliptic passes through thirteen constellations but one of them, the Serpent, is not part of the Zodiac.

Volcanoes at the origin of life. The volcanoes are probably the key to the origins of life on our planet. The volcanoes have brought to the surface of the earth, heat, water and a powerful cocktail of organic compounds the origin of life.

Life of the Abyss is surprising. In the deep ocean, saw a strange world. Even in total darkness and cold of the deep, life demonstrated great tenacity. Nutrition and reproduction remain, even in extreme conditions, an absolute necessity.

Generation "oil" is on the verge of a revolution. Most of the oil in the world has formed during short periods of extreme warming, there are 90 and 150 million years. We eat today about 100 million barrels per day.

The tardigrade, over-equipped for life on Earth. The tardigrades are able to stop their metabolism and become immortal (state cryptobiosis). To enter cryptobiosis, the tardigrades retract their eight legs and is almost completely dehydrated.

Radioactivity is a phenomenon that occurs in the nucleus, in the depths of the atoms. A radioactive radiation can come extracting electrons from the biological material, if the energy radioactive particles is greater than the binding energy of the electrons.

Nuclear power and radioactive pencils. The main source of radioactivity is natural, but we have not developed the sense to detect. The uranium dioxide pellets are stacked into tubes zirconium, 4 meters long, called "pencils".

The threat of supervolcanoes. The supervolcanoes have a flat structure and it is difficult to detect. Only after explosion, when the underground magma chamber collapses, which is see the famous caldera of supervolcano.

The little story of the evolution towards the living, starts from nothing, there is 13.7 billion years before, space and time do not exist. The microscopic world and macroscopic world gathered in the evolution of the universe.

Exoplanets are by definition located outside our solar system. The search for extrasolar planets is a real
challenge for humanity, the underlying question that scientists are trying to answer is "are we alone in the Universe?".
Since the first discovery of extrasolar planets in 1995 (51 Pegasi b), a large number of space projects such as HARPS (2003), CoRoT (2006), Kepler
(2009), JWST (2018) to Darwin (2020) have obtained funding.Until 2020, the methods used to find exoplanets, are indirect methods (effect of
transit effect on the radial velocity, microlens effect ...), that is to say that exoplanets are detected only by the effects that it induces
on their star. But from 2020, with the DARWIN space project, all humanity will see an extrasolar planet directly and perhaps a exoterre. How to detect exoplanets?Transit (periodic micro-eclipse) occurs every time the planet passes between the star and the observer.
At that time, the planet obscures some of the light from the star, producing a detectable periodic dimming. This remarkable idea is used to detect
the planet and directly determine its size and its orbit. The diameter of Jupiter is 10 times smaller than the Sun, Jupiter mask so 1% of the
luminosity of the Sun as it passes in front of a distant observer. Earth it is 100 times smaller than the Sun, so do mask 1/10000th of its brightness.How to see exoplanets? With Darwin, we'll see the planet or rather its atmosphere
that reflects light from its star. Any light that is perfectly aligned with the telescopes (that of the star) will be extinguished and so the
planet can be seen without being dazzled by the nearby star. What are the biosignatures that will reveal the presence of life on distant exoplanets?
By analyzing the spectrum of light from the atmosphere of a planet, it is possible to detect the presence of chemical compounds such as carbon
dioxide (CO2), water (H2O), ozone (O3), oxygen (O2) or other ionic assembly, and therefore no organic compounds based on a carbon skeleton. CO2
in large quantities and the water would be the signature of photosynthetic activity. Oxygen has a
specific feature. This aggressive atom may not remain in a gaseous envelope around a planet because it binds very easily with metals and rocks,
to make oxides. If there is oxygen in quantity around a planet that means biotic phenomena exist.

Astronomy - The curiosity that characterizes humanity, has enabled man to understand the major astronomical phenomena and it now gives a dramatic sense stronger what is happening before our eyes.

« It is entirely possible that behind the perception of our senses, worlds are hidden of which we are unaware. » Albert Einstein (1879-1955), Nobel Prize in Physics in 1921 for his interpretation of the photoelectric effect.